1. Field of the Invention
This invention pertains to microencapsulated flavoring agents prepared by complex coacervation. More particularly, this invention pertains to microcapsules containing a core comprising an emulsion of a flavoring agent and a resin and a coating layer over the core comprising a mixture of hydrocolloid materials. The microencapsulated flavoring agents may be utilized in a wide variety of edible compositions.
2. Description of the Prior Art
Microencapsulated flavoring agents are agents in the form of microcapsules which contain a core of flavoring agent and a coating layer over the core to control the release of the flavoring agent in a predetermined and predictable manner. In addition to providing sustained release flavor and uniform flavor intensity, microencapsulation of flavoring agents also provides protection for the flavoring agent from moisture, light, oxidizing agents, and other environmental factors.
Microencapsulation also permits the physical and chemical characteristics of a flavoring agent such as a flavor oil to be changed. For example, the hydrophobic properties of flavor oils cause the oils to irreversibly bind to gum base and certain confectionery bulking agents resulting in loss of flavor intensity and nonuniform mixtures. Conversion of such flavor oils to flavor powders by encapsulation can prevent such binding.
U.S. Pat. No. 4,597,959, issued to Barr, discloses a method for releasing flavor material in a breath freshener which comprises forming a wafer of microencapsulated droplets in an adhesive carrier. The microencapsulated droplets comprise liquid flavoring material in an amount from 85% to 90% and an encapsulating material of cross-linked gelatin and gum arabic in an amount of 5% to 15%, by weight.
U.S. Pat. No. 4,568,560, issued to Schoebel and assigned to Warner-Lambert Company, discloses a method for preparing a controlled release encapsulated active agent which comprises spray coating the active agent with a coating composition comprising a water-insoluble film-forming agent, an enteric agent, and a plasticizing agent.
U.S. Pat. No. 3,949,096, issued to Johnson et al. and assigned to SCM Corporation, discloses an improvement in a process for spray drying encapsulated particles which comprises cooling the spray dried particles while suspended in a stream of gas to prevent agglomeration. The coating materials in the process may be a saccharide material, proteinaceous material, edible gums and starches, edible waxes, edible resins, and normally solid lipoidal material.
U.S. Pat. Nos. 2,809,895 and 3,041,180, both issued to Swisher and assigned to Sunkist Growers, Inc., disclose a process for preparing an essential oil solid emulsion which comprises heating and melting a corn syrup solids solution, then adding to the melt a dispersing agent, and an essential oil containing an oil antioxidant, and then emulsifying and drying the resulting composition.
U.S. Pat. No. 4,610,890, issued to Miller et al. and assigned to Sunkist Growers, Inc., discloses a process for preparing an extruded essential oil solid emulsion which comprises heating an aqueous mixture of a sugar, a starch hydrolysate and an emulsifier, then admixing an essential oil to the aqueous mixture, and extruding the homogeneous melt into a cool solvent.
U.S. Pat. No. 3,949,096, issued to Barnes et al. and assigned to SCM Corporation, discloses a particulate composition comprising a matrix composition with up to about 40% loading wherein the matrix comprises from about 5 parts to about 95 parts maltodextrin and from about 95 parts to about 5 parts of hydrogen octenyl butanedioate amylodextrin.
U.S. Pat. No. 3,949,096, issued to Johnson et al. and assigned to SCM Corporation, discloses a composition comprising a coconut core coated with a mixture of sugar particles and sugar particles encapsulated in edible fat.
U.S. Pat. No. 3,949,096, issued to Koene et al. and assigned to Naarden International N.V., discloses a process for flavoring dry vegetable matter which comprises mixing the vegetable material with a microencapsulated flavoring agent and an adhesive solution. The microencapsulated flavoring agent consists of droplets of flavor oils coated by an envelope of edible hydrocolloids.
U.S. Pat. No. 3,704,137, issued to Beck, discloses a process for preparing a particulate flavor oil which comprises mixing and heating an aqueous mixture of sucrose, hydrolyzed cereal solids and an emulsifier, then admixing an essential oil, and extruding and cooling the melt.
United Kingdom patent application no. 2,204,553A, to National Research Development Corporation, discloses microcapsules prepared by coacervation wherein the coating material comprises gelatin and polysaccharide XM6 obtained from bacteria.
Thus, a variety of encapsulated flavoring agents are known which have specific flavoring intensities and properties. There is still a need, however, for flavoring compositions which have varying properties, enhanced flavoring intensities and delayed sustained release properties for use in ingestible compositions. Such encapsulated flavoring agents would control flavor release and would permit an ingestible composition to contain a reduced total amount of flavoring composition and thereby reduce costs, and stability problems. The present invention provides such encapsulated flavoring agents and the ingestible compositions and chewing gum products in which the encapsulated flavoring agents may be used.